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18kW Electric Tankless Water Heater, APUS 240V Instant On-Demand Hot Water Heater, Up to 4.4 GPM with LED Display, Energy-Saving Whole House Water Heating System, Space-Saving Design,Gray

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$239.99 Why this price?
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, May 14
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Set name: AP-18kW,Gray


Features

  • Enjoy continuous hot water whenever you need it. The 18kW tankless water heater electric delivers up to 4.4 GPM for 23 uses at once, such as showers, sinks, or laundry. No preheating, no waiting, and no temperature drops
  • Adjust your preferred temperature between 86F140F using the LED digital display with 1F accuracy. The electric water heater built-in memory keeps your settings even after power outages. Self-modulating technology optimizes power usage based on flow rate, ensuring stable temperature and lower energy waste
  • Achieving 99.8% thermal efficiency, this electric hot water heater on-demand water heater heats only when water flowscutting up to 60% on energy bills. Zero standby heat loss and an anti-scale interior extend lifespan and maintain strong performance for eco-conscious households
  • This tankless hot water heater ultra-slim wall-mounted heater (17.72" 11.42" 3.54") saves up to 90% more space compared to traditional tanks. With 3/4" NPT connections and 240 V compatibility(requires 340 A breakers,610 AWG cable), installation is easy and flexibleideal for whole-house or point-of-use setups in bathrooms, kitchens, or laundry rooms
  • Engineered with 6-layer protection, including anti-leakage, overheat, and surge safeguards. The separated water-electricity design prevents corrosion and ensures long-term reliability

Brand: APUS


Power Source: Breaker:3 x 40 AMP,Cable Required:6x10AWG, Hard Wiring Required


Product Dimensions: 11.42"W x 17.72"H


Special Feature: 24/7 Customer Service and Warranty, Demand Hot Water, High Efficiency, Separation of Water and Electricity, ±1°F Stable Temperature Control See more


Color: AP-18kW,Gray


Power Source: Breaker:3 x 40 AMP,Cable Required:6x10AWG, Hard Wiring Required


Special Features: 24/7 Customer Service and Warranty, Demand Hot Water, High Efficiency, Separation of Water and Electricity, ±1°F Stable Temperature Control


Wattage: 18000 watts


Voltage: 240 Volts


Maximum Temperature: 140 Degrees Fahrenheit


Efficiency: 99.8% thermal efficiency


Mount Type: Wall


Is Electric: Yes


Item Dimensions W x H: 11.42"W x 17.72"H


Material Type: Sheet Metal with Insulating Paint


Brand Name: APUS


Model Number: AP- ADSK-180G13


Manufacturer: APUS


Included Components: Water heater x1; Instruction manual x1; Rubber x5;Screw x5; Installation guide card x1; φ24×3 sealing ring x2


Unit Count: 1.0 Count


Color: AP-18kW,Gray


Style Name: AP-18kW


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, May 14

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Professional quality and excellent value.
Set name: AP-27kW,Gray
Bought this for a client's home. It’s a powerful 27kW unit that delivers consistent hot water. Much more affordable than big-box store brands but works just as well. The digital display is user-friendly and the gray finish looks premium. Great choice for any home renovation.
Reviewed in the United States on May 1, 2026 by Rong

  • Nice choice!
So far so good, works excellent, you'll need fittings from your local supplier and make sure you tighten them well to prevent any leaks. Be careful with your heat setting as this thing will heat water to a scalding temperature!
Reviewed in the United States on April 17, 2026 by Fast Eddie

  • Constant hot water no wait time for heating.
Set name: AP-18kW,Gray
I have been using a Tankless Water Heater for many years and this one was a replacement for my old one and so far works great.
Reviewed in the United States on April 25, 2026 by AgnesC

  • Works great
Set name: AP-18kW,Gray
Working great. Easy to install
Reviewed in the United States on March 23, 2026 by TJ Friar

  • Temp range misleading
Set name: AP-18kW,Gray
Unit will not reach 140°@4gpm unless in coming water is already at 90° per customer support. Other then that it's a good unit. So if you own a garden tub and want to keep your wife happy don't but this one
Reviewed in the United States on April 12, 2026 by wesley chappell

  • Great product and super customer service
After an error of installation on my part, caused the unit to not work. Customer service sent me a replacement free of charge even though it was my fault. Installed the replacement correctly and it worked perfectly. This company stood behind their product. Super customer service. I would highly recommend them. ... show more
Reviewed in the United States on March 24, 2026 by j9wern

  • Fast shipping, fairy easy to hook up.
Set name: AP-18kW,Gray
I bought a house and the water heater was leaking. Had the water company turn off the water. Ive replaced everything with pex and installed a water shut off under the house, installed this heater. Now waiting on the water company to turn the water back on. Will update if I have issues. Simple enough to install. ... show more
Reviewed in the United States on January 12, 2026 by Chappy

  • Great product
Set name: AP-27kW,Gray
Worked wonderfuly
Reviewed in the United States on March 23, 2026 by Stump

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